1. Field of the Invention
The subject flush activation system is generally directed to a system for selectively actuating a toilet flush. More specifically, the subject flush activation system is directed to a system which simply, efficiently, and reliably enables the selective activation of various flush modes that respectively consume varying volumes of water.
Water conservation remains a point of universal concern around the World. So significant is the concern in certain regions that severe use restrictions and pervasive equipment/facilities regulations are not uncommon in many jurisdictions.
A source of substantial water consumption, at least in the more modernized regions of the world, remains water-flushed toilet facilities. Given their obvious necessity, curtailing usage does not, in most cases, constitute a viable option towards water conservation. Controlling the means of their usage, however, does constitute a viable and, indeed, advisable option. Accordingly, regulations such as that limiting the maximum volume of water stored within a flush tank at any given time have been widely instituted, especially in the United States.
Beyond such regulations, further controls may be implemented to minimize the volume of water consumed in a particular flush. Depending on the composition and quantity of waste to be removed from a toilet by a given flush, the volume of water required may be selectively varied. Rather than draining the full content of the toilet's flush tank indiscriminately with every flush; the flush tank's content may be partially drained where only liquid and/or small amounts of solid waste are to be removed, and more fully drained where greater amounts of solid waste are to be removed. The potential for conserving water by controlling the toilet flush operation in this manner is quite significant, given the far greater frequency with which flushes are typically activated to remove merely liquid waste than to remove both liquid and solid wastes.
In order to realize the enormous potential for water conservation thus available, a flush activation system that is reliable enough in operation yet simple (and inexpensive) enough for quick, convenient installation into existing toilet flush system designs is necessary. Given the inherent operation of commonly employed gravity flow toilets, and the restrictive mechanical (and aesthetic) confines within which their interacting components are disposed, though, attaining a suitable flush activation system remains no trivial matter. The need remains for a sufficiently simple and efficient, yet reliable and easily-installed flush activation system for selectively varying the volume of water drained from a given flush tank by a flush.
2. Prior Art
Mechanisms for variably controlling a toilet's flush are known in the art. The best prior art known to Applicant includes U.S. Pat. Nos. 5,459,885; 5,206,960; 5,903,391; 5,511,253; 5,450,634; 5,331,690; 5,303,728; 5,205,000; 4,864,665; 4,837,867; 4,080,668; 4,829,605; 4,145,774; 3,981,029; 3,945,056; 3,894,299; 3,839,746; 5,887,292; 5,881,399; 5,699,563; 5,673,440; 5,642,533; 5,555,573; 5,524,297; 5,465,432; 5,319,809; 5,301,373; 5,157,795; 5,005,225; 4,878,256; 4,937,894; 4,651,359; 4,561,131; 4,433,445; 4,172,299; 4,149,283; 4,135,263; 4,096,591; 3,906,554; 3,903,550; 3,877,082; 3,858,250; and, 5,067,180. Such known mechanisms, however, fail to provide the sufficient combination of simplicity, efficiency, reliability and ease of installation for optimum practicability.
U.S. Pat. No. 5,459,885, for instance, discloses a dual flush mechanism for a toilet which enables both full and partial flush actuation. The mechanism employs a flush activation arm coupled by a transverse shaft to a handle. The free end of this flush activation arm is connected to a flush float which, in turn, is connected to a non-buoyant flush valve. A partial flush is effected by pivotally displacing the handle which, in turn, pivotally displaces the flush activation arm such that its free end lifts open the flush valve. The buoyancy of the flush float 26 then maintains the flush valve in this open position until the water level drops below it. At that point, the flush float falls by the force of gravity to permit the closure of the flush valve.
A full flush is effected through additional components which, when activated, blocks the flush activation arm from returning to its rest, or original, orientation. The additional components include a contoured contact plate (70) coupled to a pivot assembly (64) from which a rod (62) formed with a second flush float extends. This contact plate (70) bears against the terminal end of a control bar (40) which extends radially from the shaft connecting the handle (36) and flush activation arm (28).
When the control bar (40) is displaced during a partial flush responsive simply to a pivotal displacement of the handle (36), its tip remains thus engaged with the contact plate (70). When the control bar (40) is displaced during a full flush responsive to both an axial and a pivotal displacement of the handle (36), though, its tip proceeds to disengage from the contact plate (70), freeing that contact plate (70) for displacement beyond that tip. At that point, the rod (62) and the second flush float (60) which had been retained in the vertical orientation are freed to swing together upward, causing a laterally extended portion of the contact plate (70) to bear against and support a bottom edge of the control bar (40). This then maintains the shaft (38) and the flush activation arm (28) from returning to their non-activated orientations until the water level within the tank (12) drops sufficiently below the second flush float (60). It is only after the water level falls to a sufficiently low level that the rod (62) and second flush float (60) return to their vertical, or rest, position--to concurrently permit the contact plate's return to its original position.
A number of significant drawbacks are readily apparent in this mechanism. Perhaps the most significant is the fact that the mechanism demands a high degree of precision in its implementation. For example, the rod (62) must return fully to its vertical position before the contact plate (70) may disengage the bottom edge of the control bar (40), then re-engage the tip thereof. That is, the partial flush actuation function cannot be used again until and unless the rod (62) is permitted to return to its fully vertical position. This affords very little tolerance in such things as the length of the chains linking the flush valve (16) and the flush activation arm (28) (via the float 26). If even a slight bit of slack is present in these chains, for example, the slack may be sufficient to permit the flush valve's premature closure (before the water level has dropped enough for the second flush float (60) to descend to the point where it places the rod (62) in its fully vertical orientation). With the flush valve (16) closed, water would again begin filling the tank (12), again urging the second flush float (60) and rod (62) away from that fully vertical position, back to its activating position. Hence, the partial flush actuation function cannot be used again after the initial occurrence of a full flush without manual intervention by a user, and all subsequent flushes remain exclusively full flushes.
Another drawback is found in the frictional engagement of the control bar (40) against the contact plate (70). The cumulative effects of such frictional engagement repetitively occurring over an extended period of use would eventually lead to pronounced erosion in the engaging surfaces. Consequently, both the smooth operation and the structural integrity would be severely compromised.
Yet another drawback may be found in the relative complexity of the required motion for actuating a full flush. The concurrent pushing and turning of the handle 36 that is necessary may prohibitively difficult to some users.